body{
  margin: 0px;
  border: 0px;
  padding: 0px;
}
#top_nav{
    width: 100%;
    height: 60px;
    background-color: #00EE00;
    margin: 0 auto; 
    position: absolute; 
    z-index: 2;
}
#left_nav{
  height: 100% ;
  width: 65px;
  background-color: #C0FF3E;
  position: fixed;
  margin: 0 auto;
    z-index: 1;

}
#top_logo{
    height: 100%;
    left: 65px;
    width: 172px;
    position: absolute;
    
    
}
#main_iframe{
    width: 100%;
    height: 100%;
    margin:0;
    bottom: 100px;
    
}
#main{
    position:absolute;
    top:60px;
    left: 65px;
    bottom: 100px;
    right: 0px;
    padding: 0px;
    height: 100%;
    width: 100%-0;
}

#tail{
    background-image: url( "https://cdn.luogu.org/images/bg-footer.png");
    height: 100px;
    width: 100%;
    position: absolute;
    top:100%;
    z-index: 0;
    left: 65px;
}
.top_menu{
    position: fixed;
    left: 230px;
    z-index: 3;
    display:inline;
}
#menu_ul
{
list-style-type:none;
}
.menu_il
{
display:inline;
}
a:link,a:visited
{
font-weight:bold;
color:#FFFFFF;
background-color:#98bf21;
text-align:center;
padding:6px;
text-decoration:none;
text-transform:uppercase;
}
a:hover,a:active
{
background-color:#7A991A;
}